History NightmareFuel / ScoobyDooMysteryIncorporated

* Episode 42, "[[Recap/ScoobyDooMysteryIncS2E16AliensAmongUs Aliens Among Us". At the end of the episode, after coming upon their first clue regarding the Cursed Treasure, the gang return to Crystal Cove to see that the City Hall (and their base of operations) is up in flames and destroyed. And it was Brad and Judy who had caused the attack in the first place.

* Almost the entirety of the episode "[[ScoobyDooMysteryIncS2E10NightTerrors Night Terrors]]". Holy crap. It's basically The Mystery Gang meets ''Film/TheShining'', complete with dangerous phantasms, haunted rooms, and insane ghosts.

* The baby dolls from the doll factory in "The Wrath of the Krampus" are ''[[http://i.imgur.com/PNEoZ.jpg extremely]]'' [[http://i.imgur.com/MFgjT.jpg unsettling]].
* ''Anything'' that involves "Nibiru". Nibiru is a cataclysmic event involving a celestial object colliding with the Earth, documented in Sumerian and Babylonian mythology. In-universe, its linked with beings from the same mythology known as Annunaki. One of these is sealed within a crystal coffin which is the centerpiece of the "treasure of Crystal Cove". It has cursed the Planespheric Disk to corrupt people and animals with greed and drive them to seek out the other pieces of the Disk, which will lead them to the treasure, thus leading them to releasing him from the coffin. He will then proceed to make Earth collide with his home world.

* Episode 42, "Aliens Among Us." At the end of the episode, after coming upon their first clue regarding the Cursed Treasure, the gang return to Crystal Cove to see that the City Hall (and their base of operations) is up in flames and destroyed. And it was Brad and Judy who had caused the attack in the first place.
* Episode 43, "The Horrible Herd", full-stop. The Skull Cattle are monstrous, ravenous herds of bio-genetically mutated bovine drones (combined from cow, piranha, and bee DNA), eating anything and everything in sight, including reducing Crystal Cove to ruins. They only acted on instinct, and to provide for their singular queen, but it was ''Professor Pericles'' who used Mr. E's company and funds to create these horrific monstrosities. Proving once again that he is more desperate than ever to kill the gang, ''especially'' when the plan goes awry too, with Mr. E himself saying that Pericles has gone too far with this plan! He is now officially more evil than Fred Jones Sr.!

* Episode 44, "Dance of the Undead", besides seeing hypnotized citizens dancing themselves towards catatonia, having people buried alive in coffins, and seeing the kidnapped victims being dragged down into the earth feet-first, we do have another warning about the impending apocalypse, courtesy of the flatlined Nova in a raspy monotone. Nova, just a reminder, is a totally ordinary dog who ''cannot talk''.

* Episode 45, "The Devouring": Professor Pericles reveals that he has injected Ricky with mutated cobra venom, which he can release in small doses whenever he feels like at the push of a button, in order to keep him in line. And remember, Pericles has already killed Ed Machine and Cassidy, so Ricky is well aware of what Pericles is capable of.

* From Episode 47, "The Man In The Mirror", Pericles appears to know exactly that there is an interdimensional monstrosity sealed with the cursed treasure and is actively trying to find the treasure so he can free it, because apparently, the sealed creature is Pericles' ''master''. Mr. E, Brad, and Judy seem to have no idea they're helping Pericles unleash an EldritchAbomination onto the world.

* In ''Nightmare In Red'', we learn that those that succumb to the curse have the best part of themselves trapped in a realm between realms, and that is why Fred Jones Sr. and the original Mystery Incorporated members went so bad.

* In ''Gates of Gloom'', it's shown that the closer the old Mystery Incorporated get to the treasure, the more unraveled they become. Even [[SickeninglySweethearts Brad and Judy]] are starting to get irritated at each other.

* "Come Undone", ''everything'' relating to the Nibiru Entity.

* In the first episode, the Slime Mutant (pictured above) traps a bunch of bystanders in pods, and the bodies are so grotesque that for a while the characters think they're ''dead''. [[RRatedOpening This is an immediate sign that this show is NOT fucking around]].
* Episode 2 has a few scary moments, like the monster Gator People/Creeping Creatures chasing the gang mostly in the dark and when one of the gators shot their arm through the floor boards and grabbed Velma's foot and started to pull her down! The way they chased Scooby into the house was disturbing and trippy, and it was earlier shown through a billboard the words "The Dog Dies". Especially since this specific line [[{{Foreshadowing}} comes into play in a much later episode]]... All in all, the gators were some of the most violent monsters to appear on the show.

* Episode 3 has the Ghost Truck, with its horrifying wail.

* Episode 17, "Escape from Mystery Manor". The ruins of the Darrow Mansion are filled to the brim with Fred Jones-level booby traps, except for the fact that Danny Darrow himself used every known sharp object and weapon to try to murder his intruders, a.k.a. Scooby and the gang.

** Danny Darrow himself. He doesn't even look ''human''.

* In episode 31, "The Hodag of Horror", the Hodag wrecks havoc at a party the Blakes' are throwing, dragging a decent number of the guests, kicking and screaming, into the shadows. Sure we eventually find out it was only trying to steal their expensive jewelry but before that is revealed, all we hear are the guests screaming bloody murder while they are been dragged into the darkness. A scene straight out of a monster horror movie.

* In "The Night On Haunted Mountain", the final shot of the episode has the Captain saying "Nibiru...", who then fades away, laughing, implying that he is [[RealAfterAll a very, very real ghost]].
* Almost the entirety of the episode "Night Terrors". Holy crap. It's basically The Mystery Gang meets ''Film/TheShining'', complete with dangerous phantasms, haunted rooms, and insane ghosts.
* The episode "The Midnight Zone" may also qualify as one of the darkest entries in the series. Apart from the "child robots," testifying to a truly deranged mind, we have not only Cassidy presumably dying, but we have Professor Pericles actively ''trying to kill the gang''. He tries drowning them, tries getting them murdered by the robots, and attempts to blow up the base with the gang inside. And then last but not least, the dead body of Abigail Gluck: sitting in the control room, meaning she died alone surrounded by robots, a dead, decomposing body that sags a little on the chair when moved, and somehow ''whispers one solitary word'' to the gang.

* In the first episode, the Slime Mutant (pictured above) traps a bunch of bystanders in pods, and the bodies are so grotesque that for a while the characters think they're ''dead''. [[RRatedOpening This is an immediate sign the this show is NOT fucking around]].

** [[spoiler:Mr. E's statement is actually a misdirection; he was talking about Fred Jones ''Senior'', as he was using Fred Jr. as blackmail to keep them out of Crystal Cove.]]

** The CosmicRetcon itself is unnerving to the gang, and likely to the audience after 52 episodes of getting to know the ins-and-outs of Crystal Cove. Daphne's sisters have seemingly been made into failures, Fred's selfishly monstrous parents are now people who bring children into the world happily, Shaggy's parents ''respect him'' and even Professor Pericles has seemingly had a HeelFaceTurn into a pleasant life with Ricky Owens and Cassidy Williams. Everything is simply wrong despite having gone the whole mile and then some to EarnYourHappyEnding, and our own heroes are flabbergasted, confused and somewhat horrified.

* How about this? Shaggy's mom states that they're going to take Scooby to a nice farm. Well, that sounds nice and dandy...if it weren't for two factors: 1) Scooby will be taken away from Shaggy while Shaggy is in military school and 2) the look in the mother's eyes and her evil smile when she says that. Think about the implications...

* In the first episode, the Slime Mutant (pictured above) traps a bunch of bystanders in pods, and the bodies are so grotesque that for a while the characters think they're ''dead''. This is an immediate sign the this show is NOT fucking around.

--> '''Freak of Crystal Cove:''' From six to one, the spell is spun, no time to run, the ''curse begun''

** [[spoiler:Mr. E's statement is actually a misdirection; he was talking about Fred Jones ''Senior'', as he was using Fred Jr. as blackmail to keep them out of Crystal Cove. Which can still be seen as AdultFear from their perspective, until we actually get to know them.]]